Is there a way to size a stack child automatically to its largest sibling?
I.e. if I have a Stack with a ListTile and a Container on top, how do I make sure the Container covers the entire ListTile?
Example:
new Stack(children: <Widget>[
new ListTile(
leading: new AssetImage('foo.jpg'),
title: new Text('Bar'),
subtitle: new Text('yipeee'),
isThreeLine: true,
),
new Container(color: Colors.grey, child: new Text('foo'))
],
)
I tried to make it work with Row, Column and Expanded but am running into problems with unbounded constraints.
Is there a way to size the Container (or any other widget such as a GestureDetector) to its largest sibling in the stack?
I had the same issue and finally managed to solve it using this answer:
Inside your Stack, you should wrap your background widget in a Positioned.fill.
return new Stack(
children: <Widget>[
new Positioned.fill(
child: background,
),
foreground,
],
);
-- Mary, https://stackoverflow.com/a/45745479
Applying that to your question results in the following:
Stack(
children: <Widget>[
ListTile(
leading: AssetImage('foo.jpg'),
title: Text('Bar'),
subtitle: Text('yipeee'),
isThreeLine: true,
),
Positioned.fill(
child: Container(color: Colors.grey, child: Text('foo')),
),
],
),
Related
I have this design, The first section in the red box is fixed height size, and The second section is the dynamic height (ListviewBuilder) which changed the content based on the tabBar.
My question is How can I use the TabBar view inside the scrollable widget (custom scroll view/listview etc..)
the solution That I currently found is to use a customScrollView and use SliverFillRemaining like that
SliverFillRemaining(
child: TabBarView(
children: [],
),
),
but that adds extra white space at the bottom of the list and I can't remove it by
making hasScrollBody property false
You could probably achieve what you want with this kind of template :
Scaffold(
body: Column(
children: [
Container(
height: MediaQuery.of(context).size.height * .33,
child: Container(/* Content of the first section */),
),
Expanded(
child: DefaultTabController(
length: 2,
child: CustomScrollView(
slivers: [
SliverToBoxAdapter(
child: Container(
height: 50,
child: TabBar(
tabs: [Text("Guest"), Text("Service")],
),
),
),
SliverFillRemaining(
child: TabBarView(
children: [
// Your ListView Builder here
],
),
),
],
),
),
),
],
),
);
Seeing the bit of code you posted, it is probably close to what you already have but after test it doesn't adds extra white space at the bottom.
If it continue to display the same behavior, adding a little more context could help us provide a more accurate answer.
Flutter Web
So I have a button called add tags which opens up a modal. The Modal has only one text field and two buttons called add another tag and submit.
Now what I want to do is when the user clicks the add another tag button the app will generate another text field.
I've already seen some videos and read the documentation but since I need to work on a modal and the modal has defined size I'm not sure how to handle issues like
What happens if the user adds a lot of tags. How can I make the modal scrollable?
I'm new to flutter_form_builder so I'm not sure if the modal can handle it or not.
Here's my code:
final _formKey = GlobalKey<FormBuilderState>();
Future buildAddTagsForm(BuildContext context,
{Function()? notifyParent}) async {
return await showDialog(
barrierDismissible: false,
barrierColor: Colors.black.withOpacity(0.5),
context: context,
builder: (context) {
var screen = MediaQuery.of(context).size;
return StatefulBuilder(
builder: (context, setState) {
return AlertDialog(
content: SingleChildScrollView(
child: Container(
height: screen.height / 2,
width: screen.height > 650 ? 600.00 : screen.height * 1,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: FormBuilder(
key: _formKey,
autovalidateMode: AutovalidateMode.onUserInteraction,
child: Column(
crossAxisAlignment: CrossAxisAlignment.end,
mainAxisAlignment: MainAxisAlignment.start,
mainAxisSize: MainAxisSize.min,
children: [
Row(
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
IconButton(
onPressed: () {
Navigator.pop(context);
},
icon: Icon(
Icons.cancel_presentation_rounded,
),
),
],
),
SizedBox(
height: 10,
),
FormBuilderTextField(
name: 'Tag Name',
decoration: InputDecoration(labelText: 'Tag name'),
validator: FormBuilderValidators.compose([
FormBuilderValidators.required(context),
]),
),
SizedBox(
height: 10,
),
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
MaterialButton(
color: CustomColors.buttonColor,
child: Text(
"Add another tag",
style: TextStyle(
color: Colors.white,
),
),
onPressed: () {},
)
],
),
SizedBox(
height: 10,
),
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
MaterialButton(
color: CustomColors.buttonColor,
child: Text(
"Submit",
style: TextStyle(
color: Colors.white,
),
),
onPressed: () {},
)
],
),
],
),
),
),
),
),
);
},
);
},
);
}
I'm assuming by "modal" we're talking about the AlertDialog here:
return AlertDialog(
content: SingleChildScrollView(
By using SingleChildScrollView as the AlertDialog content:, we can have any size / any number of text fields we like in the dialog. If their number are too many for the height of dialog inside our screen, the content will scroll.
Although, its immediate child Container with height prevents the SingleChildScrollView from doing its magic:
return AlertDialog(
content: SingleChildScrollView(
child: Container(
height: screen.height / 2,
I think the above AlertDialog would not scroll because it would never be big enough to need to scroll. Plus, any fields added that combine to be taller than that specified height (screen.height / 2) will cause an overflow warning and be cutoff visually.
So to answer question #1: "What happens if the user adds a lot of tags. How can I make the modal scrollable?"
using SingleChildScrollView is the right idea
lets swap the position of the Container with height and the SingleChildScrollView and this should allow the dialog to grow & scroll as needed as columns in FormBuilder increase
Your question #2: "I'm new to flutter_form_builder so I'm not sure if the modal can handle it or not."
flutter_form_builder shouldn't affect how SingleChildScrollView works
Example
Here's a partial example of an AlertDialog with scroll view content: that can grow in number.
Widget build(BuildContext context) {
return Container(
height: 300,
child: AlertDialog(
content: SingleChildScrollView(
child: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: items,
),
),
),
actions: [
OutlinedButton(
child: Text('Add Row'),
onPressed: _incrementCounter
)
]
),
);
}
The complete example runnable in DartPard is here. (Add a 6 or 7 rows and then scroll the content.)
Warning
There's a gotcha with using the above AlertDialog inside a sized Container. That Container with height is not enough to constrain the AlertDialog size.
Your showDialog builder: (that pushes the AlertDialog into existence) must provide additional constraints in order for the sized Container to have constraints to size itself within. Without these constraints, the AlertDialog will grow until it matches the device viewport size. I believe this is a quirk with how showDialog is written, since I'm guessing it's a modal layer on top of the current stack of routes. (Someone can correct me if I'm wrong.) It's only constraint is the physical device, but nothing else. By wrapping builder:'s output with a constraining widget (such as Center) the output will be able to size itself.
To see this in action, remove the Center widget from the full example above an re-run it. The dialog will grow to fill the screen when adding rows instead of being at max 300px in height.
child: OutlinedButton(
child: Text('Open Dialog'),
onPressed: () => showDialog(
context: context,
builder: (context) => Center(child: MyDialog())
),
)
I need to fix a minimum width to my Column Widgets. Inside each of them, I have Text Widgets which can be very short or very long. I need to fix a minimum width to them in order to have an acceptable size of Column even if the text is short. The other Column need obviously to adapt himself.
Row(children: [
Column(
children: [
Container(
constraints: BoxConstraints(minWidth: 80), // do not work
child: Text("short text"),
),
],
),
Column(
children: [
Container(
constraints: BoxConstraints(minWidth: 110), // do not work
child: RichText(
text: TextSpan(
text:"very very longggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg text")),
),
],
),
],
)
There's probably a dozen ways to do what you want. And likely none of them straightforward or easy to understand. (The subject of constraints & sizes is quite complicated. See this constraints page for more examples & explanations.)
Here's one potential solution.
This will set a minimum width for the blue column (based on stepWidth), but will expand/grow if the text (child) inside wants to.
The yellow column will resize to accommodate the blue column.
class ExpandedRowPage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Expanded Row Page'),
),
body: SafeArea(
child: Center(
child: Row(
children: [
IntrinsicWidth(
stepWidth: 100,
// BLUE Column
child: Container(
color: Colors.lightBlueAccent,
child: Column(
children: [
//Text('Short'),
Text('shrt')
],
)
),
),
// YELLOW Column
Flexible(
child: Container(
alignment: Alignment.center,
color: Colors.yellow,
child: Column(
children: [
Text('Very lonnnnnnnnnnnnnnnnnnnnnnnnnnnng texttttttttttttt'),
],
)
),
)
],
)
),
),
);
}
}
You could do the above without a Flexible yellow column, but a very long text child would cause an Overflow warning without a Flexible or Expanded wrapping widget.
A Row widget by itself has an infinite width constraint. So if a child wants to be bigger than screen width, it can, and will cause an overflow. (Try removing Flexible above and rebuild to see.)
Flexible and Expanded, used only inside Row & Column (or Flex, their superclass), checks screen width and other widgets inside a Row, and provides its children with a defined constraint size instead of infinite. Children (inside Flexible/Expanded) can now look up to parent for a constraint and size themselves accordingly.
A Text widget for example, will wrap its text when it's too wide for constraints given by Flexible/Expanded.
use FittedBox();
suppose Example:
Row(
children: [
Column(
children: [
Container(
constraints: BoxConstraints(minWidth: 80), // do not work
child: Text("short text"),
),
],
),
Column(
children: [
Container(
constraints: BoxConstraints(minWidth: 110), // do not work
child:
FittedBox(
child: RichText(
text: TextSpan(
text:
"very very longggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg text")),
),
),
],
),
],
);
I was working with a drawer which had a list of tiles. Each individual tile has an image and a text following it. So I put the above mentioned widgets in a row. To my surprise, I found that there is some unexplained padding between the text and the title. I am attaching a screenshot of a tile for better understanding :
Any suggestion is welcome!. Thank you!.
I have added rowChildren which is a list of widgets because my list tile title may contain text and some image :
child = new Container(
child: new Column(
children: <Widget>[
new ListTile(
dense: true,
leading: new Image.asset(
leading,
color: Colors.white,
)
title: new Row(
children: rowChildren,
),
)
],
),
);
and this is the flutter inspector screenshot corresponding to the image I shared :
I added debugPaintSizeEnabled=true and got this :
how about using contentPadding
ListTile(
contentPadding:EdgeInsets.all(0),
dense: true,
leading: new Image.asset(
leading,
color: Colors.white,
),
title: new Row(
children: rowChildren,
),
),
I fixed it!!!.The solution is, Instead of giving the leading image in leading attribute, add it in the same rowChildren. The gap disappears!
List<Widget> rowChildren = [];
rowChildren.add(
PaddingUtils.embedInPadding(
new Image.asset(
$imagePath,
),
new EdgeInsets.only(right: 8.0)),
);
I would like to have a static bottom bar for my app.
This bar should content the hour of a device in the middle, and the temperature read by another device on the right side.
My problem is just about the positioning/sizing.
When I start it (with android studio, on real or virtual device), it doesn't work : the preview is not what I excepted, the dimensions I choose seem to have changed.
But when I hot-reload it, it becomes exactly what I want like this :
The problem is that the final app is not the hot-reloaded one ..
I may have identify the problem,
I use a MediaQuery.of(context).size and a builder to obtain the context in order to fit with all the devices considering the size. This solution must be a dirty one but I don't find anything else..
Here is my code, hope the situation is clear...
return new MediaQuery(
data: MediaQueryData.fromWindow(ui.window),
child: Builder(
builder: (context) {
return new Builder(
builder: (
context) {
return
new MaterialApp(
home: new DefaultTabController(
length: 6,
child: Scaffold(
bottomNavigationBar:
new Container(
color: Colors.white,
width: MediaQuery.of(context).size.width,
height: MediaQuery.of(context).size.height*0.1,
alignment: Alignment.centerRight,
child: new Container(
color: Colors.blue,
width: MediaQuery.of(context).size.width* 2/3,
alignment: Alignment.centerRight,
child: new Row(
children: <Widget>[
new Expanded(child: new Container(
color : Colors.yellow,
child: new Text('22 : 22' ),
alignment: Alignment.center,
)),
new Expanded(child:new Container(
color: Colors.pink,
child: new Text(' 37.8 °C'),
margin: new EdgeInsets.all(MediaQuery.of(context).size.width*0.02),
alignment: Alignment.centerRight,
))
],
),
),
),
Thank you for helping.
You could use a Stack and position one of the widget absolute over the other one:
new Stack(
children: <Widget> [
new Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget> [
new Text(time),
],
),
new Row(
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget> [
new Text(temperature)
],
),
],
),
where time & temperature are variables that were set within the state (Stateful Widgets). Then just include it in bottomNavigationBar.
I eventually added my previous code in a StatelessWidget and call it in the bottomNavigationBar field of the Scaffold : it does the job.
And I call MediaQuery.of(context) within the StatelessWidget created
Thank you.